Mine face traversing mining head



N O S R E D N A R A MINE FACE TRAVERSING MINING HEAD Original Filed May 5, 1951 4 Sheets-Sheet 1 VEN TO 1% AewoEAuosesou A. 30, 1960 A. R. ANDERSON MINE FACE TRAVERSING MINING HEAD 4 Sheets-Sheet 2 Original Filed May 5, 1951 T: .m: AN:

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MINE FACE TRAVERSING MINING HEAD Original Filed May 5 1951 4 Sheets-Sheet 4 United States MINE FACE TRAVERSING MINING HEAD Arvid R. Anderson, Upper Arlington, Ohio, assignor, by mesne assignments, to The Calomol Company, a corporation of Ohio 3 Claims. (Cl. 262-7) This invention relates to a continuous mining and loading machine or a combination loading and coal mining machine which is adapted to remove coal from the face of a mine room, gather the removed coal, and load it into a mine car, shuttle car, conveyer, or the like, at the rear of the machine.

This invention is a division of United States Patent 2,776,126 issued January 1, 1957 for Mine Face Travers ing Mining Head.

An object of the invention, therefore, is to provide an improved mining machine of the above general type.

Another object of the invention is to provide an improved mining machine of the above-described general type whereby coal removed from the mine room face, as set forth in the foregoing object, falls from the mine room face and is gathered by conveyer means adjacent the mine room floor, said conveyer means preferably, but not necessarily, trimming and smoothing the mine room floor and gathering the coal removed in so doing.

Another object of the invention is to provide an improved mining machine as set forth in the foregoing objects wherein a coal mining mechanism adapted to break, cut, tear, or otherwise remove coal from a mine room face is so disposed and moved as to travel continuously, but in different directions, over the mine room face as it is operated to remove coal therefrom.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawings:

Fig. 1 is a side view in elevation with a fragment broken away of combination cutting and loading machine incorporating features of the invention;

Fig. 2 is a view in plan, with a fragment broken away of the machine shown in Fig. 1;

' Fig. 3 is a view in elevation of the front of the machine with parts omitted;

Fig. 4 is a view, partly in section and partly in elevation, the section being taken on line 4-4 of Fig. 1;

Fig. 5 is a view in section through a fragment of the mining machine, showing particularly the construction of an adjustable eccentric mechanism the section being taken on line 5-5 of Fig. 1; and

Fig. 6 is a view in elevation looking at the rear of the head section of the machine.

In the accompanying drawings there is shown one embodiment of the combination coal cutting and loading machine, which includes a basic loader which, unless otherwise described, is identical in construction and operation to the apparatus described in the application of Sterling C. Moon, United States Patent 2,793,848 issued May 28, 1957, for a Continuous Mining and Loading Machine.

Referring to the embodiment of the machine shown in Figs. 1 through 6 of the drawings, the machine includes a truck portion having a main frame 20 that is supported, propelled forwardly or rearwardly and steered by a pair of crawler devices 21, one of which is positioned at each side of the main frame 20. The center portion of the main frame 20 forms a machinery compartment in which there is housed a hydraulic pump, gearing, clutches and the like (not shown) that are driven by an electric motor carried upon the rear end of the main frame 20'.

Adjacent its forward end, the machine is provided with what is essentially a pair of spaced apart loader bars 24 and 25 which have the double function of tearing and gathering coal from the mine floor and conveying the loose coal rearwardly to the receiving end of a receiving or discharge conveyer designated by the reference character 26 in Fig. 2 of the drawings.

The receiving or discharge conveyer 26 extends over the top of the machinery compartment to discharge at the rear of the machine.

The loader bars 24 and 25 have their rear ends connected to form a unit by the front end of main frame 20 and they slope upwardly thereon and terminate over the front or receiving end of the receiving or discharge conveyer 26. The bottoms of the loader bars 24 and 25 are spaced above the main frame 20 so that a coal conveying trough or way 37 is formed between the two bars 24 and 25, and the main frame 20 forms the bottom of aid trough or way at its rear portion. While the rear portion of each bar 24 and 25 is stationary with respect to the main frame 20, the principal portion of each of said bars, including the centrally upwardly sloping portion and the front generally horizontal portion, is pivotally mounted as a unit about a transverse horizontal axis so that the central and forward portions of said bars 24 and 25 can be adjusted about said horizontal axis, thus adjusting the position of them with respect to the mine floor.

Pivotal mounting of said central and forward portions of the bars 24 and 25 is provided by spaced pivot joints between a common bottom plate frame member 38 (see Fig. l) which rigidly and permanently connects the central portion of the bars 24 and 25. The conveyer bottom plate 38 is provided with pivot arms, one of which is indicated at 39, that are pivoted to the front end of main frame 20 by pivot joints which are seen at 40 in Figs. 1, 2, and 4 of the drawings. In other words, each of the bars 24 and 25 is provided with a rear portion which is rigidly connected to the main frame 20, while the central and forward portions thereof are pivotally mounted as a unit for adjustment about a transverse horizontal axis, thereby permitting the adjustment thereof with respect to said main frame 20 and the mine floor. This adjustment is accomplished by a hydraulic motor, not herein shown but which is shown and fully described in the above-identified United States patent of Sterling C. Moon.

Bars 24 and 25 carry endless gathering and loading chains 41 and 42, respectively, that are of similar structure but they travel in opposite directions, the former clockwise, the latter counterclockwise.

The chains 41 and 42 carry material gathering flights 43, some of which are provided with removable bits or picks 44 adapted to tear coal and gather it from the mine floor. These picks or bits 44 also assist the flights 43 in conveying the coal up the trough or way 37 from which it is spilled into the hopper trough section 29' and upon the front end of the receiving or discharge conveyor 26. It is, of course, evident, particularly by reference to Fig. l of the drawings, that the trough or way 37 is bottomless adjacent the forward portion wherein the bars 24 and 25 are ubstantially horizontal. Throughout this forward substantially horizontal portion of the bars 24 and 25 the mine floor forms the effective bottom of the trough or way 37 through which the coal is conveyed until it reaches the common bottom plate frame member 38 over which it travels to the main frame 20 and from the latter it is spilled upon the receiving or discharge conveyer 246.

The endless chains 41 and 42 are driven by sprockets 45 and 46, respectively, mounted above the machinery compartment 22 of the main frame 20. Because a portion of the bars 24 and 25 is swingable with respect to another portion and because the bars are curved upwardly substantially at the center of their lengths, the chains 41 and 42 are of the universal type.

It may appear that when the machine is advanced forwardly rectilinearly into coal on the mine floor that there might be left standing a thin rib or pile of compact coal that would enter the way 37 between the chains 41 and 4-2. However, in practice it has been found that vibrations of the machine and the lumps of coal being gathered and/or broken from the mine floor prevent the formation of such a rib of coal.

It may be mentioned here that the loader chains 41 and 42 are particularly adapted to gather coal from the mine room floor and that they will perform some digging and trimming particularly on coal which has been partially relieved, such as scallops of coal which may appear on the mine bottom as a result of the action of the breaking and chipping arms as hereinbefore described. The loader chains 41 and 42 are not adapted to cut a deep kerf in solid coal but they are adapted to remove a thin layer of relieved coal from the floor.

The supplemental mining mechanism 50 includes a mining machine breaking or chipping head 51 that has a gear box frame 52 supported from the main frame 21 by a frame mechanism in the form of a parallel linkage mechanism that includes a pair of spaced lower pivot links or arms 53 and 54 and an upper deck or platform like frame structure 55 including spaced side members 56 and 57. The lower pivot levers or arms 53 and 54 are each pivotally attached at their front ends to the back of gear box frame 52 through hinged mechanisms including pivot pins 58 and at their rear ends they are pivotally attached to the front end of main frame 20 by the pivot pins 40 through which the front ends of the bars 24 and 25 are mounted for swinging movement about the main frame. Pivot pins 4! are also supported by brackets 59 welded to the main frame.

Each of the lower links or arms 53 includes a downwardly rearwardly extending portion 60, seen in Fig. 1, provided with a foot or abutment 61 adapted to abut a forwardly facing surface or abutment 6-2 of the main frame to limit the lowermost position to which the levers 'or arms 53 and 54 and, consequently, the mining mechanism including the head 51 can swing.

The side members 56 and 57 of the upper deck or platform-like frame structure 55 are pivotally attached at their front ends to the back of gear box frame 52 through hinge mechanisms that include pivot pins 63, and at their rear ends the members 56 and 57 are journaled upon a power driven cross shaft 64 that is supported for rotation in bushings or bearings 65 (see Fig. carried in the ends of arms or brackets 66 that may be formed as parts of the main frame 20.

Each end of the shaft 64- carries and drives an adjustable eccentric or crank apparatus 67. Because both of these eccentric or crank apparatuses are alike, only one of them will be described in detail. Each end of shaft 64 is grooved circumferentially at 63 to provide a slot and in this slot there is placed a generally U- shaped key or retainer member 69. Outwardiy of this 'key or retainer 69 the shaft 64 is machined to provide it with a rectangular end portion 70 that is received in a rectangular opening in a wheel 71. Wheel 71 is machined to fit over and receive closely the U-shaped key or retainer 69 to prevent the latter from being removed from the groove 68 except when the wheel 71 is removed from shaft 64. Wheel 71 is secured against axial movement upon the end of shaft 64 by the key 69 and a plurality of cap screws 72, the heads of which seat in 4 the key or retainer member 69 and the bodies of which are threaded into the Wheel 71.

The outside face of the wheel 71 is machined to provide a slot that extends diametrically across it and in this slot it carries a gib bar 73 secured to the wheel 71 by three cap screws 74. The slot in wheel 71 and the gib bar 73 cooperate to provide a way 75 that receives a crank arm 76 having a journal shaft 77. The gi-b bar 73 provides a means by which the crank arms 76 may be readily adjusted and locked within the way 75.

The cross shaft 64 is driven or rotated by two power units 78 that are similar but one of which is righthanded and the other of which is left-handed. Because these units are similar, except as described, the internal structure of only one of them is herein shown and described in detail.

This power unit 78 (see Fig. 2) includes a gear speed reducer 79, the housing 8% of which is secured to the deck or platform-like frame 55 by a plurality of bolts 81 (see Fig. 1) and is journaled upon cross shaft 64. Housing carries a rotary hydraulic motor 82, the main shaft of which drives a worm 83 that meshes with and drives a worm gear 84 carried upon a shaft 85 suitably bearinged within the housing 80. Shaft 85 carries a worm 86 that meshes with and drives a second worm gear 87 mounted on a second shaft 88 also suitably bearinged within housing 8t), and which shaft carries a worm 89. Worm 89 drives a worm gear 90 that is within the housing and mounted upon the cross shaft 64 so as to drive it. The speed of motor 82 is variable and consequently the speed of cross shaft 64 may be varied as desired.

The motors 82 may be driven from the pumps 48 through appropriate conduits and they may be provided with a control valve in order that they may be started and stopped and so that their speed may be controlled while the pumps 48 continue to rotate at full speed.

This hydraulic circuit may be of any standard well known corporate conveniently into the mining machine.

The journals 77 of the adjustable eccentric or crank apparatuses 67 are each connected to a journal pin 91 on the lower links or arms 53 or 54 by links or pitman connector mechanisms 92, the lengths of which are adjustable. Each connector mechanism 92 is essentially a turnbuckle device that includes acentral sleeve 93 and a pair of bars or rods 94, one threaded into each end thereof. One of the rods 94 carries a right and the other a left hand thread so that when the sleeve 93 is rotated with respect to them the overall length of the connector assembly may be increased or decreased depending upon the direction in which the sleeve 93 is rotated. I

From the description thus far given it will be seen that when cross shaft 64 is rotated by the power units 78, the journal shafts 77 will travel or follow a circular path and that they will, accordingly, act through the links or connector mechanisms 92 to cause the arms 53 and 54, the mining mechanism including the breaking or chipping head 51 and the top deck or platform-like frame 55 to operate or swing upon the main frame 20 a parallelogram; that is, the breaking or chipping head 51 will be raised and lowered and it will at all The crank arms 76 are adjustable upon the wheel 71 to vary the vertical distance through which, the mining mechanism including the breaking or chipping head 51 will travel, and the conhector-members 92 are of variable or adjustablelength in order that the lowermost position or bottom limit of travel of the breaking or chipping head 51 may be the It will, of course, also be seen that when themachine housing 95 carried on 3 is in operation the diameter of the circles or paths in which the journal shafts 77 rotate must be substantially equal; that is, the distances between the axes of the journal shaft 77s and journal pins 91 on arms 53 and 54 must be substantially equal. In order to adjust these distances on each side of the machine the supplemental mining mechanism is caused to occupy the position seen in Fig. 1 of the drawings in which its weight will be supported by the feet or abutment 61 and abutment 62 on main frame 20. Then the screws 74 and gib 73 on each wheel 71 are loosened. The lengths of the links or connector members 92 are then adjusted to shift or adjust the crank arms 76 within the ways 75. When the length of each connector mechanism is properly determined and adjusted the screws 74 and gib bars 73 are tightened to lock the crank arms 76 to the wheels 71 and the machine may be operated.

In order to simplify the adjustment of the crank arms 76 and links or connector mechanisms 92 the connector mechanisms 92 are interconnected by mechanism which when operated to adjust one crank arm 76 and connector mechanism 92 also adjusts simultaneously the crank arm 76 and connector mechanism 92 on the opposite side of the machine. This mechanism includes a gear each sleeve 93 in which there is a worm gear 96 that is also carried by the sleeve 93 and connected to rotate it. Gear housings 95 are interconnected and prevented from rotating with respect to the sleeves 93 by a tube 97 in which there is a cross shaft 98 (see Fig. 1), the ends of which provide worms 99 that mesh with the gears 96. Thus, when shaft 98 is rotated the sleeves 93 of both of the connector mechanisms 92 are rotated to adjust the overall length of them simultaneously and the same amount. Cross shaft 98 is rotated by a removable crank, not shown, that may be inserted through either of the housings 95 and into engagement with either end of the cross shaft 98.

The main frame 52 of the breaking or chipping mining mechanism head 51 may be a casting and it, together with a front closure plate 100, forms a generally rectangular gear box or housing 101. The lower portion of gear box or housing 101 carries a plurality of spaced generally longitudinally and rectangularly extending horizontal shafts, the axes of which lie in a common generally horizontal plane, there being four such shafts illustrated in the disclosed embodiment of the invention, said shafts being designated 102, 103, 104 and 105. The four shafts 102 through 105 are geared together, and their directions of rotation are indicated by the arrows in Fig. 3 of the drawings.

The upper portion of the rectangular gear box or housing 101 carries a-plurality of shafts 106, 107, 103 and 109, which shafts are spaced directly above the lower shafts 102, 103, 104 and 105, respectively, so that their axes lie in a horizontal plane, and these shafts 106 to 109, inclusive, are parallel to the shafts 102 to 105. Shafts 106 to 109, inclusive, are geared together, as are shafts, 102 to 105, inclusive, and their directions of rotation are also indicated by arrows in Fig. 3 of the drawrugs.

Each of the upper shafts 106 to 109, inclusive, drives a coal cutter, chipper or breaker arm, said coal cutter, chipper or breaker arms being designated 110, 111, 112 and 113 and each of them includes a portion which extends generally radially from its axis of rotation which is the axis of its drive shaft. Each breaker arm 110 through 113 is preferably unbalanced with respect to said axis of rotation in that it extends radially in one direction only or for a greater amount than its radial extension in the opposite directions. Each of these breaker arms 110 through 113 is provided with a plurality of radially spaced bits 114 formed on cusps of the breaker arm. As viewed in Fig. l of the drawings, that is, in an upright plane passing through the axis of rotation of each arm 110 to 113, the bits 114 traverse 6 progressively receding paths as their distance from the axis of rotation increases. The radially innermost bit 114 of each arm 110 through 113 projects ahead or to the front of the front end of its drive shaft, as illustrated in Fig. 1, whereby it will cut coal from in front of the driving shaft.

The lower shafts 102 to 105, inclusive, carry coal cutter, chipper or breaker arms 115, 116, 117 and 118, respectively, which may be similar to the breaker arms 110 through 113, but which are illustrated as of slightly different construction in that they have longer plain hubs and they extend generally radially, with portions on opposite sides of the axis of rotation, there being two receding bits '119 on one side of the axis of rotation and another hit 120 on the side generally opposite thereof.

All of the upper breaker arms 110 through 113 are driven from a single rotary hydraulic motor 123 (see Fig. 6) which is carried by the back or rear of the gear box frame 52. The lower breaker arms 115 through 118 are driven through a mechanism that is in general identical to the mechanism that drives the upper breaker arms 110 through 113. The difference between these driving mechanisms resides in the positioning and arrangement of certain parts thereof as is made obvious from Fig. 6 of the drawings. Because these mechanisms are comprised of identical parts, only the drive mechanism for the lower breaker arms 115 through 118 need be described.

A rotary hydraulic motor 124 that is identical to the motor 123 drives the lower breaker arms 115 through 110. Hydraulic motors 123 and 124 may be driven from the pumps 48 through appropriate conduits and they may be provided with a control valve so that they may be started and stopped or their speed may be varied while the pumps 48 continue to rotate. This hydraulic circuit may be of any standard, well-known design.

The gear box or housing 52 houses a top and a bottom train of gears, which gear trains are identical. The lower gear train includes a plurality of gears that interconnect and drive the four generally horizontal longitudinally extending shafts 102, 103, 104 and which lie in a common substantiallyhorizontal plane from the power driven shaft 104. The upper gear train interconnects the four generally horizontal longitudinally extending shafts 106, 107, 108 and 109 and drives the shafts 106, 108 and 109 from the shaft 107.

The construction of the breaker arms through 113 differs in another respect from that of the breaker arms through 118, in that the hub of each of them is provided with an eccentric, that for arm 112 being seen at 127 11 Fig. 3 of the drawings. As illustrated in Fig. 3 of the drawings, the eccentrics associated with breaker arms 110 and 111 are in phase and these are 180 out of phase with the in-phase eccentrics associated with the breaker arms 112 and 113.

Carried by the eccentrics of breaker arms 110, 111 is a trimmer plate 128 that carries a row of bits 129 across its top flat, horizontal edge, the points of which extend forwardly and laterally outwardly. A similar trimmer plate 130 is carried by the eccentrics of breaker arms 112, 113 which is provided with bits 131 which also extend forwardly and laterally outwardly, the lateral direction of which is opposite the bits 129.

During rotation of the breaker arms 110 through 113 in unison the bits 129 and 131 as operated by their trimmer plates 128 and 130, respectively, will shave off any scallops which might be produced on the roof of the room by the rotating breaker arms 110 through 113, thus leaving a substantially flat smooth roof.

Referring particularly to Fig. 3 of the drawings, the breaker arms110 through 113 and 115 through 118 will rotate in the directions indicated by the arrows. As a consequence, there will be a generally balanced condition insofaras lateral thrusts ion the head 51 are concerned. Furthermore, it is important to note that the left-hand breaker arms 115 and 116 travel inwardly during the lower half of their rotation, thus conveying released coal toward the center of the machine. The breaker arms 117 118 also travel inwardly during the lower half of their rotation to convey material on the other side of the machine toward the center.

The paths of travel of the breaker arms 115 through 118 overlap those of the adjacent arms. Furthermore, as clearly illustrated in Fig. 3 of the drawings, the outer pair of breaker arms 115 and 118 cyclically extend beyond the lateral dimensions of the chipping and breaking head 51 and then laterally within said dimension so as to cut a room, entry or tunnel which has a width greater than the width of the gear box frame 52 which is also greater than the width of the main frame 20 of the machine. Similarly, the upper breaker arms 110 to 113 travel overlapping areas, each with respect to the adjacent breaker arms, and the two side breaker arms 110 and 113 cyclically extend laterally beyond the dimension of the frame 52 of head 51 and then laterally within said frame dimension and cyclically laterally beyond and within the dimension of the main frame 20 of the mining machine.

No interference is encountered between any of the breaker arms because of the fixed phase relation of each of the upper and lower groups. While the upper and lower groups are not geared together there can be no interference between them because, as illustrated in Figs. 1 and 3 of the drawings, the upper group of breaker arms 110 to 113 rotate in an area which is entirely to the rear of the area of rotation of the lower group. The arms of the upper and lower groups may, however, be geared together by simple reach gears, if desired.

In view of the above description, the mode of operation of the machine will be clear. For example, the

single driving or main electric motor 23 will supply power for operating all of the power operated devices contained in the truck or loader section of the machine and for driving all of the driven mechanisms of it. This includes operation of the hydraulic system of the truck or loader mechanism, the propelling of the crawler mechanisms 21 at a high transportation speed or at a low forward chipping or feeding speed, as well as the operation of the gathering and loading chains 41 and 42 and the discharge conveyer 26.

The machine can be operated at high speed to bring it up to the mine face and during this maneuvering a motor, not shown, elevates the trough or way 37 tomove the machine through narrow entries, around mine posts and along curved paths. The operation of the crawlers 21 provides for both forward and reverse movements of the machine as well as swinging movement of it by the individual operation of either crawler while the other is disengaged and its brake mechanism is applied.

To effect the cutting and loading operation, the machine is first fed preferably forwardly rectilinearly to adjacent the mine face. During this operation, of course, the supplemental mining mechanism 50 including the breaking and chipping head 51 is in the position indicated in full lines in Fig. 1 and in Fig. 3 of the drawings.

When the machine is adjacent the mine face the operator thereof will adjust the eccentricity or stroke of the adjustable stroke or crank apparatuses 67 by rotating the cross shaft 98. This adjustment is for fixing the top or uppermost position to which the breaking and chipping head 51 will be elevated during each cycle or revolution of the crank apparatuses 67. Said uppermost position may be at any position above the position of it, indicated in full lines in Fig. l of the drawings, up to that position of it which is indicated in dot-dash lines and is the maximum or uppermost top position which the breaking and chipping mining head 51 may occupy.

After the adjustment of the stroke has been made, i.e., the upper limit of travel of the breaking and chipping head 51 has been fixed, the mining and loading operation may be effected by setting the discharge conveyer 8 26, gathering and loading chains 41 and 42, the motors 82 and 123, 124, in operation to drive the various devices of the apparatus which operate upon the coal. 'With these things in operation the entire machine is fed for? wardly rectilineanly into the mine face at its slow or breaking, cutting, tearing, or chipping speed.

From Fig. 1 of the drawings it will be seen that the bottom row of chipping arms, including arms 115 through 118, projects ahead of the gathering and loading chains 41 and 42, and the upper row of chipping arms in that order, and that therefore these lower chipping arms 115 through 113 will be the first to operate to remove coal from the mine face as the machine is fed forwardly. It will also be seen that these lower chipping arms 115 through 118 will remove from the mine face coal from immediately above the gathering and loading chains 41 and 42 as the machine progresses forwardly into the coal at the mine face. This is important when the chains 41 and 42 are of the gathering and loading type, as shown in Fig. 1 of the drawings, because these chains 41 and 42 are not capable of cutting a deep ker-f in solid coal, and the removal of the coal immediately above that area or plane into which the chains 41 and 42 are forced relieves the weight from the coal at the mine floor. Under this condition the chains 41 and 42 are capable of tearing and dislodging the relieved coal from the floor.

The lower chipping and breaking arms 115 through 118 project ahead of the upper chipping and breaking arms through 113 and because of this they remove coal from immediately below the coal that is to be broken and otherwise removed by the upper chipping arms 110 through 113. While it is not necessary that the lower arms 115 through 118 operate upon the coal at a position ahead of the upper breaker arms 116 through 113, it is desirable that they do because it relieves load upon the upper arms 11f) through 113 by providing a space into which coal broken by them may fall and it causes the upper arms 11% through 113 to remove larger pieces of coal from the mine face since as soon as the pieces are freed from the face they may :fall upon the front end of the gathering and loading bars 24 and 25 from where they are conveyed rearwardly by chains 41 and 42 to the discharge conveyer 26. I

It will be apparent from Figs. 2 and 3 that the breaking and chipping arms remove from the mine face coal in an area that is wider than the main frame 20 of the machine, and from Figs. 1 and 3 it will be seen that even when the breaking and chipping head 51 occupies its lowermost position the breaking and chipping arms will remove from the mine face a portion of coal slightly higher than the truck portion of the machine and thus it will cut an entry, tunnel or mine room of sufficient height and width to receive the machine whereby it may follow continuously through the opening formed in the coal vein by the head 51 and breaking and loading chains 41 and 42.

When the breaking and chipping head 51 is cycled vertically its breaking and chipping arms each function in a manner similar to a router in that while they are rotating they are being advanced laterally into the coal, thus chipping and breaking the coal as they swing or sweep into it rather than boring axially into it.

The motors $2 are of variable speed in order that the rate of travel or the speed of the vertical cycle of the breaking and chipping head 51 may be varied.

I claim: 7

l. A coal mining machine comprising a self-powered mobile main frame supporting a gathering conveyer, mining mechanism for cutting and breaking coal from the coal face, linkage mechanism between said main frame and said mining mechanism to support the latter, pivot means interconnecting said linkage mechanism to said main frame and said mining mechanism,'an eccentric having a rotary. throw supported on said mainframe, a

threaded .screw and rotary sleeve mechanism therefor pivotally connected as a pitman between said eccentric and said linkage mechanism to raise and lower said mining mechanism, means for rotating said sleeve relative to said screw to raise and lower said mining mechanism, and motor means for rotating said eccentric mechanism for raising and lowering the mining mechanism.

2. A mining machine adapted to cut and remove the mined material in advancing the whole face to form a tunnel as the machine moves forward, comprising a power driven mobile main frame, a mining mechanism including a plurality of forwardly extending rotary shafts, cutting members mounted on said shafts, parallel linkage mechanism between said main frame and said mining mechanism, pivot means interconnecting said linkage mechanism to said main frame and said mining mechanism, said main frame supported pivoted means being a rotary driven pivot shaft, a driving motor for said pivot shaft carried by one link means of said linkage mechanism, an eccentric means attached to said pivot shaft and having a predetermined throw, and pitman means pivotally interconnecting said eccentric means and said other'link means of said linkage mechanism to sweep said mining mechanism while said rotary cutting members mine the whole face within the throw determined by said eccentric means and the mining machine moves forward.

3. A mining machine adapted to cut and remove the mined material in advancing the whole face to form a tunnel as the machine moves forward, comprising a power driven mobile main frame, a mining mechanism including a plurality of forwardly extending rotary shafts, cutting members mounted on said shafts, parallel linkage mechanism between said main frame and said mining mechanism, pivot means interconnecting said linkage mechanism to said main frame and said mining mecha nism, power driven rotary eccentric means supported from said frame and having a predetermined throw, and pitman means pivotally interconnecting said eccentric means and said linkage mechanism to sweep said mining mechanism while said rotary cutting members mine the whole face within the throw determined by said eccentric means and the mining machine moves forward, said pitman means including rotary screw means to change the length of said pitman means and thus regulate the opposite limits of the sweep of said mining mechanism.

References Cited in the file of this patent UNITED STATES PATENTS 1,639,012 Tillyer et a1. Aug. 16, 1927 1,757,772 Johnson May 6, 1930 1,870,906 Gottschalk Aug. 9, 1932 2,606,010 Howard Aug. 5, 1952 2,694,562 Snyder et a1 Nov. 16, 1954 2,694,563 Graham Nov. 16, 1954 2,740,618 Snyder et a1. Apr 3, 1956 2,793,848 Moon May 28, 1957 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent N0 2,950,907 August 30 1960 Arvi d R.. Anderson It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the grant, lines 2 and 12, and in the heading to the printed specification, line 4, name of assignee, for "The Calomol Company", each occurrence read The Colmol Company Signed and sealed this 25th day of April 1961.

SEA L) Attest:

ERNEST w], SWIDER I DAVID 1 LADD Attesting Officer Commissioner of Patents 

